Question

A car accelerates from rest at 2.0 m/s2 for 20 s. The speed then remains constant for 20 s, after which the car slows down with an acceleration of 3 m/s2 until the car stops. What is the total distance traveled?

Answer 1

first part
final v = a t = 40 m/s
average v = 20 m/s
x = 0 + 20(20) = 400 m

second part
v = 40
x = 400 + 40(20) = 1200 m

third part
Vi = 40
average v = 20
time = 40/3 = 13.3
x = 1200+20(13.3) = 1466 m

Answer 2

3066